German Offenlegungsschrift (Laid-Open Specification) No. 27 42 058 discloses an apparatus for applying measurement value sensors and measurement electrodes on surfaces. The apparatus comprises a suction cup which surrounds a measuring probe and which is acted upon with vacuum. While the suction cup and measuring probe are adapted for use on skin surfaces, the apparatus is limited in its usefulness in that it is not provided with any means for vertically orientating and pressing the measuring probe with a predetermined pressure.
A method of testing the final coatings on motor vehicle bodies is known from the journal "Automobil Revue" No. 13 of 27-3-1986, page 51, in which a measuring probe is guided along a body by way of automatic manipulators. The automatic manipulator required for this must be precisely controlled by way of suitable sensors, in order that it can guide the measuring sensor along the curved profile of a body. This requires a relatively complicated automatic manipulator with a very expensive sensor control device. In addition, the body must be held stationary during the measuring procedure, so that this measurement cannot be carried out in the normal production procedure of motor vehicle bodywork manufacture.
The object of the invention is to provide a method of measuring coating layer thicknesses on motor vehicle bodies in such a way the measurement can be carried out by means of simple automatic manipulators while the vehicle bodies are moving.